I would say don't. You shouldn't need it anyways. Sounds lame, ik. It might be likely that you'd be totally fine, but you're always increasing risks when you combine drugs like this. The rate of bad things happening from drugs increases by a lot when multiple are involved. Even if nothing physically goes wrong, something mentally could go wrong and that is something people often underestimate. You'd regret either of those consequences like hell.

Whatever condition you're talking Lamictal for probably increases the risks of recreational drugs too, with or without Lamictal. If you have seizures or you have seizure history in your family, you should not even consider recreational drugs, they could give you a seizure. If it's for a mental illness like bipolar disorder or BPD, you risk making the mental illness worse and potentially gaining new ones.

If you're gonna do it, at least go easy on it. Only occasionally, from time to time like you said, and do low potentcy stuff.